Metamath Proof Explorer


Theorem logimcld

Description: The imaginary part of the logarithm is in ( -upi (,] pi ) . Deduction form of logimcl . Compare logimclad . (Contributed by David Moews, 28-Feb-2017)

Ref Expression
Hypotheses logimcld.1 ⊢ ( 𝜑 → 𝑋 ∈ ℂ )
logimcld.2 ⊢ ( 𝜑 → 𝑋 ≠ 0 )
Assertion logimcld ( 𝜑 → ( - π < ( ℑ ‘ ( log ‘ 𝑋 ) ) ∧ ( ℑ ‘ ( log ‘ 𝑋 ) ) ≤ π ) )

Proof

Step Hyp Ref Expression
1 logimcld.1 ⊢ ( 𝜑 → 𝑋 ∈ ℂ )
2 logimcld.2 ⊢ ( 𝜑 → 𝑋 ≠ 0 )
3 logimcl ⊢ ( ( 𝑋 ∈ ℂ ∧ 𝑋 ≠ 0 ) → ( - π < ( ℑ ‘ ( log ‘ 𝑋 ) ) ∧ ( ℑ ‘ ( log ‘ 𝑋 ) ) ≤ π ) )
4 1 2 3 syl2anc ⊢ ( 𝜑 → ( - π < ( ℑ ‘ ( log ‘ 𝑋 ) ) ∧ ( ℑ ‘ ( log ‘ 𝑋 ) ) ≤ π ) )